Rosai-Dorfman disease (RDD) is a rare non-Langerhans cell histiocytosis characterized by massive lymphadenopathy and systemic extranodal lesions. We present the case of a 28-year-old woman who presented with recurrent blurred vision in her right eye for 3 months. She developed blindness and atrophy in her left eye a decade prior to presentation. She subsequently developed headache, fever, and impaired mental status. Cranial magnetic resonance imaging indicated hypertrophic pachymeningitis (HP), and 18F-fluoro-2-deoxy-2-d-glucose (FDG) positron emission tomography/computed tomography revealed significant FDG uptake in the left dura mater. Autoimmune testing revealed elevated anti-nuclear, anti-SS-A, and anti-SS-B antibody levels. Incisional biopsy of the atrophic eyeball revealed RDD with marked polyclonal plasmacytosis. The patient was diagnosed with RDD accompanied by multisystem involvement, including Sjögren\'s syndrome (SS), panuveitis, and HP. Treatment with methylprednisolone for several weeks resulted in significant improvement. This is the first reported case of RDD presenting with SS in combination with panuveitis and HP. Although RDD is rarely diagnosed in young patients, interdisciplinary collaboration is essential to prevent a delayed diagnosis.

Immunoglobulin G4-related disease (IgG4-RD) is an autoimmune disorder associated with fibroinflammatory conditions that can affect multiple organs. Hallmark histopathological findings of IgG4-RD include lymphocytic infiltration of IgG4-positive plasma cells, storiform fibrosis, and obliterative phlebitis. However, little is known about central nervous system involvement of IgG4-RD. Hypertrophic pachymeningitis (HP) has recently been reported as a manifestation of IgG4-RD, which may have previously been demonstrated in a significant percentage of idiopathic cases. Herein, we report a rare case of a 63-year-old male who presented with a scalp mass that mimicked a brain tumor. He was diagnosed with IgG4-related HP (IgG4-RP) after surgery. This case suggests that awareness of a possibility of IgG4-RP in patients with isolated scalp masses, even in the absence of systemic symptoms, is crucial. A combination of careful history taking, evaluation of serum IgG4-levels and imaging as an initial work-up, followed by tissue biopsy, is important for the differential diagnosis of IgG4-RP, malignancy, and other infectious diseases.

Hypertrophic pachymeningitis (HP) is a relatively rare disease of the central nervous system characterized by local or diffuse fibrous thickening of the dura mater. At present, there is still insufficient research on the pathogenesis and treatment strategies of this disease. We reported a continuous case series of seven patients with idiopathic HP (IHP), and also details one case of immunoglobulin G4-related HP requiring surgical intervention. Early diagnosis and appropriate surgical intervention for IHP could prevent the progression of permanent neurological damage and spinal cord paraplegia.

UNASSIGNED: Hypertrophic pachymeningitis (HP) is a rare inflammatory disorder characterized by local or diffuse thickening of the intracranial or spinal dura mater. The most frequent cause of HP is antineutrophil cytoplasmic antibodies (ANCA), followed by IgG4. However, few cases of IgG4-HP coexpressing ANCA have been reported. Herein, we present three cases of IgG4-HP coexpressing ANCA and review the relevant literature to document the overlap of these two HP causes as a potential clinical pattern.
UNASSIGNED: We retrospectively analyzed three patients with IgG4-HP coexpressing ANCA in our center and consulted the PubMed database to find other relevant cases reported in English from 1976 to April 2022. We used the following keywords: pachymeningitis, meningitis, dura, antineutrophil cytoplasmic antibody, myeloperoxidase, and proteinase-3. We analyzed the clinical, serological, radiological, and pathological characteristics of the obtained cases based on the ACR and Chapel Hill criteria and the exponential moving average (EMA) algorism for ANCA-associated vasculitis (AAV) and the IgG4-RD Comprehensive Diagnostic Criteria.
UNASSIGNED: We analyzed a total of 10 cases: seven literature reports and our three patients (52- and 61-year-old women and a 65-year-old man). The IgG4-related disease (IgG4-RD) diagnoses were definitive in four cases, and probable and possible in three cases. Eight patients had ANCA against myeloperoxidase (MPO), and two had ANCA against proteinase-3 (PR3). Two patients had both IgG4-RD and AAV, while the others only had ANCA seropositivity without additional clinical or pathological markers of AAV.
UNASSIGNED: With regard to HP, we reconfirmed the existence of the IgG4-RD and AAV overlap syndrome. Meanwhile, our review does not support the hypothesis that ANCA positivity in IgG4-RD results from an excessive B-cell response. We speculate that IgG4-RD and AAV have similar or associated pathogeneses, although uncovering the role of IgG4 and ANCA in these pathophysiological processes requires further investigation.

UNASSIGNED: IgG4-related disease is a rare, recently recognized chronic inflammatory disease. IgG4-related hypertrophic pachymeningitis (IgG4-RHP) of the central nervous system predominantly involves the cranial meninges. Spinal involvement remains rare.
UNASSIGNED: We report a case of recurrent cervicothoracic IgG4-RHP and review the surgical literature.
UNASSIGNED: A 35-year-old woman presented with a 6-month history of neck and right shoulder pain, progressive right triceps weakness and paresthesias in the right C8 and T1 dermatomes. MRI demonstrated a T2 hypointense epidural soft tissue mass extending from C6-T1. The patient underwent C6-T1 laminoforaminotomy and partial resection with near complete symptom resolution. Histopathology was consistent with diagnosis of IgG4-RHP. Eighteen months postoperatively, she experienced symptom recurrence necessitating re-operation and adjuvant postoperative prednisone with complete resolution at 40-months\' follow-up.
UNASSIGNED: Of the now nineteen confirmed cases of IgG4-RHP, fifteen underwent surgery. A majority achieved partial resection. Three surgical patients did not receive adjuvant therapy with symptomatic recurrence between 2 and 18 months.

We report an extremely rare case of hypertrophic pachymeningitis in which a 71-year-old man presented with an intractable recurrent headache for >1 year. During this period, he became positive for immunoglobulin G4 and proteinase 3-antineutrophil cytoplasmic antibodies. Contrast-enhanced magnetic resonance imaging showed characteristic diffuse thickening of the dura. Symptoms were improved by intravenous methylprednisolone (500 mg per day for 5 days) and cyclophosphamide pulse therapy during corticosteroid withdrawal; he remained symptom-free during 1-year follow-up. This case suggests that this disease can be treated by corticosteroids combined with immunosuppressive agents.

Hypertrophic pachymeningitis (HP) is a rare inflammatory disorder characterised by local or diffuse thickening of the cranial and spinal dura mater. HP occurs owing to idiopathic or secondary causes, including autoimmune disease, infection, and trauma. HP has mainly been reported in adults, with few reported cases in children. We encountered an 11-year-old boy with idiopathic HP who presented with chronic inflammation and daily occipital headache. Gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) helped us to diagnose him with HP. He was successfully treated with corticosteroids and azathioprine with no recurrence. We also conducted a literature review of childhood-onset HP and found only 16 cases, including our patient. Seven patients had idiopathic HP, and the remaining nine had secondary HP, including two with rheumatic disease. The most common clinical symptoms were headache (68.8%) and cranial nerve-related symptoms (68.8%). Inflammatory laboratory markers were elevated in 60% of patients with available data. Fifteen cases were diagnosed using Gd-enhanced MRI. The main initial treatment was steroids and/or immunosuppressants, to which 87.5% of patients responded. However, two patients with HP associated with trauma and neuroblastoma (12.5%) died, and seven patients (43.8%) had left cranial nerve-related sequelae. As the prognosis for childhood HP is poor, early diagnosis and treatment are essential. Children with headache, cranial nerve symptoms, and elevated inflammatory marker levels should be suspected of having HP and Gd-enhanced MRI should be considered.

Hypertrophic pachymeningitis (HP) presents with thickening of the dura mater in the cerebrum and spine, and its symptoms vary depending on the affected location. The association of HP with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis has been recognized, and most cases are complicated by granulomatosis with polyangiitis. We report the case of a 47-year-old man who presented with HP upon relapse of eosinophilic granulomatosis with polyangiitis (EGPA), with literature review. He presented with disturbance of consciousness, and magnetic resonance imaging (MRI) revealed thickening of the dura mater around the left parietal lobe. Although myeloperoxidase (MPO)-ANCA was positive on EGPA diagnosis, the elevation of MPO-ANCA was not documented at the onset of HP. Brain perfusion scintigraphy showed an increase in blood flow in the left parietal lobe and temporal lobe, and electroencephalogram (EEG) revealed slow waves in the left parietal lobe. He was treated with a high dose of corticosteroid and rituximab, and the slow waves on EEG and brain perfusion were normalized. Although the most frequent symptom of HP is headache, disturbance of consciousness can be the manifestation of HP, and inflammation of HP could affect the cerebral parenchyma, which can be documented as abnormal EEG and perfusion scintigraphy. Literature review revealed that most of the HP in EGPA developed when EGPA relapsed, and was observed in patients with MPO-ANCA positivity. HP develops without evidence of other clinical features of EGPA; therefore, adequate imaging, including contrast-enhanced MRI, is necessary. Rituximab may be effective for treating HP complicated with EGPA.

OBJECTIVE: Hypertrophic pachymeningitis is an infrequent inflammatory disease resulting in thickening and fibrosis of the dura mater. In most cases, the cause in unknown and is called idiopathic hypertrophic pachymeningitis (IHP). Audiovestibular symptoms are infrequent and the pathogenesis is still unclear.
METHODS: A systematic literature review of cases with IHP and vestibular symptoms from 2000 to February 2020 was performed. PRISMA Checklist was followed and PubMED database, Web of Science and Cochrane library were searched. We report a case of an adolescent with a diagnosis of vestibular neuritis in the context of IHP attended in our clinic.
RESULTS: We reviewed 5 articles related to IHP and vestibular disorders. A total of 7 cases (5 women and 2 men), with ages between 27 and 68 years with IHP were found. They all had audiovestibular symptoms. In contrast to our patient, uni or bilateral neurosensorial hearing loss was reported in all cases. Furthermore, there is no other case report published describing the association between IHP and vestibular neuritis. High dose steroids improved symptoms in 85.7% of the patients.
CONCLUSIONS: Vestibular symptoms in IHP are uncommon and the pathogenesis is still debatable. Entrapment of nerves in the internal auditory canal and secondary neuronal damage could be suspected as the main cause of hearing and vestibular loss.

UNASSIGNED: IgG4-related disease (IgG4RD) is a multisystemic progressive fibroinflammatory and lymphoproliferative autoimmune disorder of unknown etiopathogenesis; and its occurrence in intradural extramedullary (IDEM) location is extremely rare.
UNASSIGNED: The aim of this study was to review all IDEM IgG4RD cases described in English literature and to signify the role of surgery in its management at this rare location along with the surgical technique and intraoperative findings.
UNASSIGNED: An Internet-based search (PubMed) for the published reports describing spinal cases of IgG4RD with IDEM involvement was done using the keyword: spinal IgG4-related disease. An illustration of a case of cranial IgG4-related disease in a young man who developed metachronous cervical involvement in intradural extramedullary (IDEM) location is also presented.
UNASSIGNED: Amongst 45 spinal IgG4RD cases reported in English Literature, only 3 cases were IDEM IgG4RD. In the illustrated case, portion of the cervical lesion causing cervical cord encasement was intradural but extraarachnoidal- located between arachnoid and dura, without any pial involvement. All these 4 cases improved following surgery.
UNASSIGNED: Timely meticulous resection of mass lesion in situations of medical treatment failure or progressive neurological decline can lead to reversibility of mass effect-associated neurological manifestations of IgG4RD.